The overall objective of this clinical investigation is to identify by quantitative physiological measurements, the conditions under which selected nursing interventions directly effect observed changes in the cerebrovascular hemodynamic state of the closed head injured patient (CHIP). The speicific aims or objectives for this study are: 1) Determine through measurements of intracranial pressure (ICP), mean arterial pressure (Mean a B/P), cerebral perfusion pressure (CPP) and heart rate (HR) how each of the five designated experimental groups of CHIP will respond to the nursing interventions of endotracheal tube suctioning (ETTS). Criteria for each of the five experimental groups is based upon resting ICP and either normothermic (36 degrees C plus or minus 1 degree) or hypothermic (32 degrees C plus or minus 1 degree) state; 2) measure the effect of 14 position changes upon ICP, Mean a B/P, CPP and HR on five designated groups of CHIP. The 14 position changes include those changes in patient position necessary in carrying out nursing care of the CHIP; and 3) Document using five designated groups how the measurements of ICP, Mean a B/P, CPP and HR change during the administration of hygiene measures (Table 4) i.e., a) oral hygiene, b) body hygiene, and c) indwelling catheter care. The resarch design will be correlational. The dependent variables for all three specific objectives will be delta ICP, Mean a B/P delta CPP and delta HR. Independent variables in addition to designated groupings will be the nursing interventions of ETTs, position change and hygiene measures. Statistical methods will include (Specific Objectives 1) 3 ways all random ANOVA and (specific Objective 2 and 3) 3 way mixed model ANOVA.